SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'aade103faf4dba08c8d58fa7fb8693ae69fc36b9e129843147fbc86428140add' 
  AND token = 'eR0ytilRS9/996HxU6WuOAGMWzV3fkdH7GTkCi31t1c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}